Problem 3. (a) Find a and b such that a + x(x + 3) 2 + 3 (b) Use part (a) to compute the infinite series CO E n(n + 3) n>1 Problem 4. Consider the sequence 2n an 3n+ 1 for n > 1. (a) Is (an)n>1 convergent? (b) Is En>1 an convergent